


there will be hell to pay

by oikawakkun



Category: Haikyuu!!
Genre: Gen, Hurt/Comfort, I Love Their Sibling Dynamic So Much, Original Female Character(s) - Freeform, Original Male Character(s) - Freeform, Rated For Violence, and some cursing, no beta we just die, nothing too graphic, protective osamu
Language: English
Status: Completed
Published: 2020-07-28
Updated: 2020-07-28
Packaged: 2021-03-06 03:14:18
Rating: Teen And Up Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 1,583
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/25526515
Author URL: https://archiveofourown.org/users/oikawakkun/pseuds/oikawakkun
Summary: "Hurt him again." Osamu warns, still so quiet and cold, eyes burning with a kind of rage and intensity that he never thought he'd be able to feel towards anyone. "And I can promise you one thing. You'll be breathing through a tube for the rest of your life."
Relationships: Miya Atsumu & Miya Osamu
Comments: 28
Kudos: 331





	there will be hell to pay

**Author's Note:**

> hello! i honestly did not see this fic coming. i was so sure my first fic in ao3 would be one of my current twitter aus, but here we are. this idea would not leave my mind for the whole day and i just had to make it, so enjoy some miya twins siblings dynamic!

When Atsumu got home later than usual, it didn't bother Osamu at all. _The idiot always gets himself side tracked on his way from club practice, so it's not like this is anything new,_ Osamu reasons with himself as the minutes go by. so when Osamu finally heard the door click open and saw his twin entering their shared room, he gives himself a pat on the back for being right once again.

He was about to continue on with his manga reading but something felt off about the way his brother was walking to their bed, like it physically pained him to take even a single step forward. It worried Osamu when he saw him stumble a few more times.

"What's your problem?" Osamu asked. Finally looking up to meet his twin's face and the sight that greeted him felt like a splash of cold water. Osamu took one look at him and his face went completely blank _._ He headed straight for Atsumu, dropping the manga on the hard wooden floor in his rush.

Atsumu stood his ground on principle against Osamu's questioning gaze, even though every inch of him wanted to just lay down on their bed and sleep the aches away. His right eye was throbbing and swollen already, and even his ribs felt sore, which made walking a huge pain in the ass. He just _can't_ deal with any of Osamu's shit right now, not when everything fucking hurts.

“Back off, 'Samu,” he muttered, stepping away when his twin stopped right in front of him. They were at odds with each other most of the time and Atsumu knows it's because he always tried to push Osamu whenever he thought he could get away with it. “I didn’t start it this time, 'kay? Just saw some third years from class 5 and—”

Osamu’s hand on his face had Atsumu shutting up and his eyes darting up again to meet his twin's. There was a sea of conflicting emotions in his brother's eyes that Atsumu can't seem to understand completely. There's no way Osamu was this angry at him for something he didn't even do on purpose, Atsumu concludes, relieved that he'll probably be able to get him off his case about this and head straight to bed. He just wants to lay down and fall asleep, to forget this whole incident ever happened.

“What third years?” Osamu asked suddenly after inspecting the cuts and bruises on his face. Atsumu blinked, his pain momentarily forgotten with how Osamu's voiced dropped dangerously low at the mention of his assailants. This was definitely not how Atsumu pictured their entire conversation would go.

“They were from class 5, I think,” Atsumu starts, unsure with how he’s going to explain the whole incident to his brother without getting embarrassed for letting himself get beaten up. “They were tryin’ to get money out of Hana-san’s grandson and I told em to back off so they decided to gang up on me instead.”

It was humiliating, if Atsumu was being honest, he wan't even able to land as many hits to their faces as he wanted. But there wasn’t anything he could do against three guys twice his size. “They were gonna beat the shit out of the poor guy, and you know how nice Hana-san’s been to Ma since we moved here.” Atsumu looked away when Osamu nodded. “It just didn’t feel right if I let em do that to the him.” He finished in a whisper, too embarrassed now that his brother knows everything that happened.

Osamu made a soft sound of acknowledgement, and finally lets him go. Atsumu just stared at his twin for the longest time, gauging him for any reaction.

“Okay.” Osamu finally says and he made his way out of their room leaving Atsumu frozen in place, unsure of what to make out of his twin's sudden disappearance.

He comes back five minutes later with an ice pack and he made Atsumu hold it in place. The initial coldness made Atsumu hiss in pain but Osamu is quick to place his hand firmly on Atsumu’s so the ice pack stays on his right eye to keep the swelling down.

“What did ya mean, okay?” Atsumu starts once Osamu took the ice pack from him and made him lay down on the bed. 

Osamu sat back down on the chair near their desk as he picked the manga up from the floor and started to read once again. “Just that.” He answered, already turning away from his brother and ending their conversation.

Atsumu’s too tired to question, let alone get mad at his brother for saying such a stupid answer, so he turns his back to Osamu and starts to fall asleep. What he failed to notice was the relentless shaking of Osamu’s hands as he gripped the manga too tightly.

\---

It was too easy to spot the three third years when they made their presence so damn obvious. Osamu almost laughs when he sees one of them smoking despite being within school grounds. _What a bunch of assholes._

“Are you guys from class 5?” Osamu asked once he’s in front of them, making sure he’s blocking their sight. That got their attention quickly and the guy sitting in the middle lazily passes his eyes over Osamu, like Osamu’s very presence was an eyesore to him. He exhales a breath of smoke and motions for the guy sitting next to him to take charge.

“The fuck do you want speaking to your seniors like that?” The other guy on his right asked, making his way to grab Osamu by the collar. Osamu easily avoids it and side steps the incoming punch from the guy and lands his own right on the guy's cheek. Osamu felt a satisfying crack from the impact of his fist on the guy's skin and the guy falls to the ground, unconscious.

“Hey, ain’t he the guy talkin' shit who we beat up yesterday?” Osamu heard the other one whisper to who he assumes is the leader and he looks at the two and smiles, all teeth.

“Nah, you got two things wrong.” Osamu answered, already pulling the second guy away from the leader to land a punch to his face. “One, I’m actually that guy’s twin brother,” Osamu starts as he lands a swift kick to the guy’s side. “And two, you guys messed with the wrong twin. And now, you have to deal with _me_.” He finished as the second guy falls down with a cry and a broken nose.

The leader laughs, sounding too amused when Osamu turned his glare at him. “Look, kid, you look pretty smart for a first year. So let me give you some advice.” He starts with a sigh, as he took another drag of his cigarette despite the bloody scene right in from of him, like it doesn't concern him at all. “You can’t just walk up to your seniors all high and mighty like what yer brother did." He said, finally standing up to show off his full size, towering over Osamu when he stood right in front of him. "Ya gotta show us some respect, otherwise little brats like you and _him_ would get—”

But he didn’t get to finish his sentence. Because at that moment, while he was still talking, Osamu already had him pinned to the ground.

His punches are hard and heavy, relentless as he continues to leave a trail of blood every time he raises his firsts to land another blow to the guy’s face. He does this enough times that he could feel his skin splitting apart from the constant contact. The pain on his knuckles finally got to him and he stops to stand up from his crouch and dusts off his slacks, not minding the blood covering his knuckles which weren't his own. He hears their pain filled sobs echo within the otherwise empty courtyard and feels a sense of satisfaction for causing it.

"No, let me give _you_ some advice.” Osamu starts, eyes downcast and merciless as he watched the three beaten up bodies laying motionless on the ground.

"Hurt him again." Osamu warns, still so quiet and cold, eyes burning with a kind of rage and intensity that he never thought he'd be able to feel towards anyone. "And I can promise you one thing. You'll be breathing through a tube for the rest of your life."

The image of Atsumu badly beaten up will forever haunt Osamu in his sleep and just the thought of it sent a shiver down his spine. He wasn't able to do his job properly yesterday, and he's never going to let that happen a second time. Atsumu should never look like that, _ever._ And if anyone dared to try and hurt him again, there _will_ be hell to pay.

\---

Atsumu greeted him when he got back home, the bruises and cuts still fresh on his face and Osamu can't seem to look at him for too long.

"What the hell happened to yer hands 'Samu?" Atsumu shouted, already inspecting the bandages on his knuckles with a look full of worry. "I'm fine, 'Tsumu." Osamu answered, pushing his brother away to head up stairs for a change of clothes.

"Is this cause of me?" Osamu heard him ask, voice soft with something raw and tender. He stops walking and looks up to meet Atsumu's eyes.

"Always." Osamu answered with a smile.

**Author's Note:**

> Not really sure what time line to fit this to.. but rest assured, Osamu will always be there for his bother, no matter what! also, i hc that osamu's way stronger than what people give him credit for.


End file.
